GET /v1/models #

Retrieve available Nellie AI models and their credit costs.

Overview #

This endpoint returns a list of available Nellie AI models with their names, descriptions, and credit costs per book. Use it to display model options to users or calculate expected costs.

Endpoint #

GET https://api.nelliewriter.com/v1/models

Authentication #

Not required. This is a public endpoint.

Example Request #

cURL #

curl https://api.nelliewriter.com/v1/models

Python SDK #

from nellie_api import Nellie

client = Nellie(api_key="nel_your_api_key")
models = client.get_models()

for model in models:
    print(f"{model.name}: {model.cost_per_book} credits")

Python (requests) #

import requests

response = requests.get("https://api.nelliewriter.com/v1/models")
data = response.json()

for model in data["data"]:
    print(f"{model['name']}: {model['cost_per_book']} credits")

JavaScript #

const response = await fetch('https://api.nelliewriter.com/v1/models');
const { data } = await response.json();

data.forEach(model => {
  console.log(`${model.name}: ${model.cost_per_book} credits`);
});

Response #

Success (200 OK) #

{
  "success": true,
  "data": [
    {
      "id": "2.0",
      "name": "Nellie 2.0 (Standard)",
      "description": "Balanced performance for fast standard books.",
      "cost_per_book": 250
    },
    {
      "id": "3.0",
      "name": "Nellie 3.0 (Premium)",
      "description": "Higher creativity and coherence for complex plots.",
      "cost_per_book": 500
    }
  ]
}

Response Fields #

Available Models #

Nellie 2.0 (Standard) #

Best for:

• Standard novels
• High-volume generation
• Cost-conscious projects
• Bulk generation

Nellie 3.0 (Premium) #

Property	Value
ID	"3.0"
Cost	500 credits
Speed	Slower
Quality	Excellent

Best for:

• Complex narratives with multiple plot threads
• Character-driven dramas
• Projects requiring high coherence
• Professional-quality output

Model Comparison #

Feature	Nellie 2.0	Nellie 3.0
Cost	250 credits	500 credits
Speed	~20-30 min	~45-80 min
Plot complexity	Good	Excellent
Character depth	Great	Excellent
Coherence	Excellent	Excellent
Creativity	Great	Excellent
Image Quality	Good	Excellent

Use Cases #

Display Model Selector #

async function displayModelOptions() {
  const response = await fetch('https://api.nelliewriter.com/v1/models');
  const { data } = await response.json();
  
  const container = document.getElementById('model-options');
  
  data.forEach(model => {
    const card = document.createElement('div');
    card.innerHTML = `
      
${model.name} #
      
${model.description}
      
${model.cost_per_book} credits
      Select
    `;
    container.appendChild(card);
  });
}

Calculate Expected Cost #

import requests

def estimate_cost(model_id: str, include_images: bool = False) -> int:
    ""Estimate the credit cost for a generation.""
    response = requests.get("https://api.nelliewriter.com/v1/models")
    models = {m["id"]: m for m in response.json()["data"]}
    
    if model_id not in models:
        raise ValueError(f"Unknown model: {model_id}")
    
    base_cost = models[model_id]["cost_per_book"]
    
    # Images add approximately 50% to the cost
    if include_images:
        base_cost = int(base_cost * 1.5)
    
    return base_cost

# Usage
cost = estimate_cost("3.0", include_images=True)
print(f"Estimated cost: {cost} credits")

Pre-flight Cost Check #

from nellie_api import Nellie

client = Nellie(api_key="nel_...")

# Get user's credits
usage = client.get_usage()
available = 10000 - usage.total_credits_used  # Assuming 10 credits

# Get model cost
models = client.get_models()
model_3 = next(m for m in models if m.id == "3.0")

if available >= model_3.cost_per_book:
    book = client.books.create(
        prompt="A sci-fi epic",
        model="3.0"
    )
else:
    print(f"Insufficient credits. Need {model_3.cost_per_book}, have {available}")

Credit Costs #

The cost_per_book is the base cost.

Related Endpoints #

• POST /v1/book — Use model ID when creating books
• GET /v1/usage — Check your credit balance
• GET /v1/configuration — Get other valid parameters

See Also #

• Rate Limits & Credits — Understanding the credit system
• FAQ — Common questions about pricing